System and method for monitoring vacuum valve closing condition in vacuum processing system

ABSTRACT

A system and method for cleaning and inspecting ring frames is disclosed here. In one embodiment, a vacuum valve comprising at least one sealing O-ring; and a pressure monitoring tape on a mating surface on a vacuum processing chamber, wherein the pressure monitoring tape is configured to perform a pressure profile mapping between the mating surface on the vacuum processing chamber and a surface of the at least one sealing O-ring on the vacuum valve to determine a closing condition of the vacuum valve.

This application is a continuation of U.S. patent application Ser. No.16/521,989, filed Jul. 25, 2019, which claims benefit of priority toU.S. Provisional Patent Application No. 62/711,398, filed Jul. 27, 2018,the entireties of each are referenced herein.

BACKGROUND

In the semiconductor integrated circuit (IC) industry, there is acontinuing demand for smaller device dimensions and higher circuitpacking densities. This demand has driven the semiconductor industry todevelop new materials and complex processes. For example, when a feature(e.g., a gate/drain/source feature of a transistor, a horizontalinterconnect line, or a vertical via, etc.) is to be formed on a wafer,the wafer typically goes through a production line which comprisesmultiple processing stations typically using different process tools toperform various operations such as cleaning, photolithography,dielectric deposition, dry/wet etching, and metal deposition, forexample.

A “killer defect” caused by particles can occur on a semiconductorsurface in one or more aforementioned malfunctioning processing stationsalong the production line. In a vacuum processing station, particles canbe introduced to a vacuum processing chamber from one or more vacuumvalves due to its misalignment with a mating surface on a vacuum chamber(e.g., leakage, friction, etc.). In general, inspection of vacuum valvesis manually performed by a human to determine their closing condition(e.g., alignment and pressure). Such manual inspection of vacuum valveshas a poor resolution. Further, such a “manual” inspection ofteninterrupts an automatic production line, which also increases thepossibility of wafer contamination.

Therefore, in contrast to the manual inspection, an automatic inspectionof vacuum valves that can detect their closing conditions to providecritical insights into a wide variety of process characteristics (e.g.,tools and conditions), without significantly interrupting the productionline or affecting its throughput, has been desired by the IC industry.Despite this long felt need, no suitable systems meeting theserequirements are available.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that various features are not necessarily drawn to scale. In fact,the dimensions and geometries of the various features may be arbitrarilyincreased or reduced for clarity of illustration.

FIG. 1 illustrates a cross-sectional overview of a vacuum processingsystem, in accordance with some embodiments of the present disclosure.

FIG. 2A illustrates a cross-sectional view of a pressure monitoring tapefor monitoring a closing condition of a vacuum valve with an o-ring on abottom surface for sealing with a mating surface on a vacuum processingchamber, in accordance with some embodiments of the present disclosure.

FIG. 2B illustrates a cross-sectional view of a pressure monitoring tapefor monitoring a closing condition of a vacuum valve with an o-ring on aside surface for sealing with a mating surface on a vacuum processingchamber, in accordance with some embodiments of the present disclosure.

FIG. 3 illustrates a cross-sectional view of a monitoring system formonitoring the closing condition of a vacuum valve in a vacuumprocessing system, in accordance with some embodiments of the presentdisclosure.

FIG. 4 illustrates a flowchart of a method to use a pressure monitoringsensing tape in a vacuum processing system to monitor the closingcondition of a vacuum valve in a vacuum processing chamber, inaccordance with some embodiments of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following disclosure describes various exemplary embodiments forimplementing different features of the subject matter. Specific examplesof components and arrangements are described below to simplify thepresent disclosure. These are, of course, merely examples and are notintended to be limiting. For example, it will be understood that when anelement is referred to as being “connected to” or “coupled to” anotherelement, it may be directly connected to or coupled to the otherelement, or one or more intervening elements may be present.

The presented disclosure provides various embodiments of a method andsystem for monitoring a closing condition of a vacuum valve in a vacuumprocessing system. A vacuum valve widely used in vacuum processes needsto be inspected to prevent potential particle contamination caused byfriction or leakage caused by a misalignment between the valve and themating surface as part of a chamber wall. Traditionally, a valve and itsalignment to the mating surface are inspected by a manual inspection.Such manual inspection of vacuum valves typically has a poor resolution.Further, such a “manual” inspection often interrupts an automaticproduction line, which also increases the possibility of wafercontamination. In contrast to the traditional manual inspection, asystem and method to automatically detect the alignment of a vacuumvalve and its mating surface can provide critical insights into a widevariety of process characteristics (e.g., tools and conditions) withoutsignificantly interrupting the production line or affecting itsthroughput has been desired by the IC industry is presented.Accordingly, the above-mentioned issues may be advantageously avoided.

This description of the exemplary embodiments is set to be understood inconnection with the figures of the accompanying drawing, which are to beconsidered part of the entire written description. In the description,relative terms such as “lower,” “upper,” “horizontal,” “vertical,”“above,” “below,” “up,” “down,” “top” and “bottom” as well asderivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,”etc.) should be construed to refer to the orientation as then describedor as shown in the drawing under discussion. These relative terms arefor convenience of description and do not require that the apparatus beconstructed or operated in a particular orientation.

FIG. 1 illustrates a cross-sectional overview of a vacuum processingsystem 100, in accordance with some embodiments of the presentdisclosure. The vacuum processing system 100 comprises a vacuumprocessing chamber 102 which can be a physical vapor deposition (PVD)chamber or a chemical vapor deposition (CVD) chamber, according to someembodiments. In some embodiments, the physical vapor deposition chambercan be used in a DC magnetron sputtering system, a plasma enhancedsputtering system, etc. In some embodiments, the vacuum processingchamber 102 can be an atomic layer deposition (ALD) chamber. In someother embodiments, the vacuum processing chamber 102 can be used for dryetching processes, e.g., deep reactive ion etching (DRIE). In someembodiments, the vacuum processing chamber 102 can be connected to aload lock chamber (not shown) and further to the ambient environment orto another vacuum processing chamber (not shown). The vacuum processingchamber 102 comprises at least one transfer port 104 with acorresponding vacuum valve 106, at least one vacuum port 108 connectedto a pressure control unit 110 (e.g., vacuum pump). In some embodiments,the vacuum processing chamber 102 can comprise at least one gas-feedingport, a temperature control unit, a power control unit, a matchingcircuit depending on the application and system. In some embodiments,the gas through the gas-feeding port to the processing chamber 102 mayinclude at least one or a combination of O₂, Ar, N₂, H₂, NH₃, N₂O, CF₄,SF₆, CCl₄, CH₄, H₂S, SiH₄, metal-containing precursors, etc. Althoughnot shown in the figure, for the ones with ordinary skill in the art itis understandable that the vacuum processing chamber 102 may be alsoequipped with a plurality of pressure gauges, thickness monitor systems(quartz crystal monitor, spectroscopic ellipsometer, reflectionhigh-energy electron diffraction detector (RHEED)), shutters, arotational manipulator, viewports, transfer ports, etc.

According to the exemplary embodiment described herein, the vacuumprocessing system 100 can be used in processing the surface layers of asemiconductor wafer 112. For example, any of a photoresist layer, masklayer, or other layer of a semiconductor wafer as desired, can beprocessed before or after an etch step, or any combination thereof,according to a specified recipe. The recipe also specifies parametersused to establish the proper environment in the vacuum processingchamber 102 for realizing the desired features and feature dimensions onthe semiconductor wafer 112. The recipe can specify a type of reactantgas to be introduced into the vacuum processing chamber 102 and its flowrate, a pressure during reaction, a temperature and a power.

Referring to FIG. 1, the semiconductor wafer 112 that can be transferredthrough the transfer port 104 to the vacuum processing chamber 102 fordesired processes. In some embodiments, the vacuum valve 106 comprises amechanism to provide an opening and a closing motion to the vacuumvalve. In some embodiments, the vacuum processing system 100 furthercomprises a wafer transfer mechanism 114 for loading the semiconductorwafer 112 to and unloading the semiconductor wafer 112 from a waferstage 116 in the vacuum processing chamber 102. The semiconductor wafer112 may be a bulk silicon substrate although other semiconductormaterials including group M, group IV, and group V elements may also beused. Alternatively, the semiconductor wafer 102 may be asilicon-on-insulator (SOI) substrate. In some embodiments, a devicelayer may be a polysilicon layer (not shown) disposed on thesemiconductor wafer for the formation of one or more polysilicon gatesin the wafer. In another embodiment, the device layer may be ametallization layer such as an inter-layer dielectric (ILD) or aninter-metal dielectric layer (IMD) for forming interconnect structures(e.g., metal lines and/or vias). In yet other embodiments, the devicelayer may be any layer in the semiconductor wafer 112 that may bepatterned using photolithography and etching processes. The wafer mayinclude numerous device layers. Furthermore, the device layer mayinclude a buffer layer (e.g., an oxide interfacial layer, not shown), anetch stop layer (e.g., a silicon nitride layer, a silicon carbide layer,or the like), or the like. A hard mask may be formed over the devicelayer for use as a patterning mask. The hard mask may comprise an oxide,silicon oxynitride (SiON), silicon nitride (Si₃N₄), titanium nitride(TiN), or the like.

FIG. 2A illustrates a cross-sectional view of a pressure monitoring tape208 for monitoring a closing condition of a vacuum valve 106 with ano-ring 204 on a bottom surface for sealing with a mating surface 206 ona vacuum processing chamber 102, in accordance with some embodiments ofthe present disclosure. In some embodiments, the vacuum valve 106 is atransfer valve, a transfer door, a gate valve, a pendulum valve, etc.with a single-axis or a multi-axis closing mechanism. In someembodiment, the axis 201 along which the vacuum valve 106 closes isperpendicular to the transfer port 104. In some embodiments, thetransfer port 104 for transferring semiconductor wafers 112 can be indifferent shapes, for example, rectangular triangular, and hexagonalaccording to the process configurations. In some embodiments, the vacuumvalve 106 can be made of stainless steel. In some embodiments, thevacuum valve 106 can be made of aluminum for magnetic sensitiveprocesses.

Different type of seals can be used between the vacuum valve 106 and apressure sensing tape 208 on the mating surface 206 on the vacuumprocessing chamber 102, e.g., on a flange, depending on the pressurerange and application. O-rings are the most frequently used of allseals. In the illustrated embodiments, an o-ring 204 can be made ofelastomers with different hardness. In some embodiments, the hardness ofthe o-ring 204 is selected so that the o-ring 204 can adapt to theunevenness of the mating surfaces 206 to ensure a seamless contact. Thesurface of the o-ring 204 is free of releasing grease, smooth andcrack/scratch-free. In some embodiments, the o-ring 204 is coated with athin film of a low vapor pressure grease (e.g., silicon grease, mineraloil based or perfluoropolyether-based grease), which is used to smoothout small irregularities on the surface of the o-ring 204 and thepressure sensing tape 208 on the mating surface 206. In someembodiments, the cord diameter of the o-ring 204 is in a range of 2-12millimeter (mm), which is selected to ensure that the o-ring 204provides a proper sealing effect and is not excessively compressed. Insome embodiments, the o-ring 204 is placed in axial or a radial grooves202 depending on the closing motion of the valve relative to the matingsurface. In some embodiments, the o-ring groove 202 is larger than thediameter of the o-ring 204 to ensure a secured assembly. In someembodiments, a plurality of o-rings 204 in o-ring grooves 202 can beconfigured on the vacuum valve 106.

In some embodiments, at a closed state of the vacuum valve 106, theo-ring 204 is aligned with the pressure monitoring tape 208 so that thepressure monitoring tape 208 can measure the pressure between the o-ring104 and the mating surface 206 to evaluate the alignment and thepressure of the vacuum valve 106. In some embodiments, the pressuremonitoring tape 208 comprises a plurality of sensing elements configuredas an array. In some embodiments, each of the plurality of sensingelements comprises thin film sensors with a thickness of 10 microns toseveral hundreds of microns. In some embodiments, the back of thepressure monitoring tape 208 comprises adhesives that allow a facileintegration to the mating surface 206 on the vacuum processing chamber102. In some embodiments, the adhesive is vacuum grade and has low vaporpressure to avoid degassing into the vacuum system. In some embodiments,the pressure monitoring tape 208 is flexible. In some embodiments, thesensing element 308 in the pressure monitoring tape 208 can detect thecontact and measure the surface contact pressure between the surface ofthe o-ring 204 and the mating surface 206 once properly calibrated. Thesensing element is a tactile force sensor which can be based ondifferent technologies and materials, for example, capacitive,piezoresistive, which will be discussed further in detail below in FIG.4.

FIG. 2B illustrates a cross-sectional view of a pressure monitoring tape208 for monitoring a closing condition of a vacuum valve 106 with ano-ring 204 on a side surface for sealing with a mating surface 206 on avacuum processing chamber 102, in accordance with some embodiments ofthe present disclosure. In some embodiments, the closing motion of thevacuum valve 106 (e.g., single axis gate valve or a pendulum valve) canbe along an axis 201 that is not perpendicular to the transfer port 104.The o-ring 204 in the o-ring groove 202 can be on the edge surface ofthe vacuum valve 106 to make a proper seal with the mating surface 206.The pressure monitoring tape 208 is configured on the mating surface 206according to the position of the o-ring 204. In the illustratedembodiment, the pressure monitoring tape 208 is placed on the innersurface of a flange attached to the transfer port 104.

FIG. 3 illustrates a cross-sectional view of a monitoring system 300 formonitoring the closing condition of a vacuum valve 106 in a vacuumprocessing system 100, in accordance with some embodiments of thepresent disclosure. The pressure monitoring system 300 comprises apressure monitoring tape 208 on a mating surface 206, a data acquisitionunit 310, a data processing unit 312, a local computer 314 and adeposition control unit 316, according to the illustrated embodiment.

The pressure monitoring tape 208 comprises an array of sensing elements304. In some embodiments the sensing element 304 is a tactile sensorbased on various technologies. In some embodiments, the sensing element304 can be a capacitive tactile sensor with two parallel plates, inwhich the applied force can change the charge stored in the capacitor bychanging the distance between the two parallel plates. In someembodiments, the sensing element 304 can be a piezoelectric tactilesensor, in which an electrical potential is formed according to theapplied stress or strain. In some embodiments, the sensing element 304can be a piezoresistive tactile sensor, in which the resistivity changeaccording to the applied stress or strain. In some embodiments, thesensing element 304 can be fabricated using a CMOS (complementarymetal-oxide-semiconductor) technology on semiconductors. Although threeare 3 sensing elements in one row shown in the illustrated embodiment,it should be noted that any number of sensing elements in a row and anynumber of columns/rows in an array can be used and are within the scopeof this disclosure. The array of sensing elements is configuredaccording to the size/number of the sensing elements 304 and requirementof the spatial resolution.

The array of sensing element 304 in the pressure monitoring tape 208 canbe coated with a protective coating 302. Proper calibration is requiredto compensate a constant drift of change of properties (e.g.,capacitance, resistance, etc.) under a constant pressure for a prolongedduration of time. In some embodiments, the sensing element 304 is aflexible film pressure sensor or an electronic skin. In someembodiments, the sensing element is protected by a flexible thin film ora Teflon coating.

The array of sensing element 304 is then connected to a data acquisitionunit 310, according to some embodiments. The data acquisition unit 310comprises a scanning circuit, an address generator, a decoder, etc.,which allows a readout from each sensing element 304 in the array. Thescan speed across the entire array can be a few tens of kilohertz andcan be configured by users according to the number of sensing elementsand their response time. The data acquisition unit 310 is furtherconnected to a data processing unit 312 and a local computer 314, wherethe measurement data can be processed by an analog-to-digital (A/D)converter, displayed and stored on a local computer.

The data can be displayed in real-time on the screen of the localcomputer 314 to monitor the closing process of the vacuum chamber, thestatus of the vacuum valve 106, the contacting area between surfaces inorder to convert measured force to pressure. Furthermore, the systempresented here can also provide opportunities to monitor the lifetime ofthe o-ring 204 for early detection of failure in o-ring 204 to preventleakage or contamination to the vacuum processing system 100.

In addition to the pressure distribution, the local computer 314 can befurther configured to obtain an average pressure value, a maximumpressure value, a minimum pressure value and a deviation of pressurevalues. In some embodiments, these values can be compared to predefinedor user-preconfigured threshold values in order to determine whether aprocess in the vacuum processing chamber 102 can be performed. If avalue is within a predefined or user-preconfigured threshold value, thelocal computer 314 can further instruct the vacuum processing controlunit 316 to perform the vacuum processing. If a value is out of apredefined or user-preconfigures threshold value, the local computer 314can further alarm the operator and trigger a preconfigured maintenanceprocedure.

The control unit 316 is a representative device and may comprise aprocessor, a memory, an input/output interface, a communicationsinterface, and a system bus. The processor may comprise any processingcircuitry operative to control the operations and performance of thecontrol unit 316 of the system 100. In various aspects, the processormay be implemented as a general purpose processor, a chip multiprocessor(CMP), a dedicated processor, an embedded processor, a digital signalprocessor (DSP), a network processor, an input/output (I/O) processor, amedia access control (MAC) processor, a radio baseband processor, aco-processor, a microprocessor such as a complex instruction setcomputer (CISC) microprocessor, a reduced instruction set computing(RISC) microprocessor, and/or a very long instruction word (VLIW)microprocessor, or other processing device. The processor also may beimplemented by a controller, a microcontroller, an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA), aprogrammable logic device (PLD), and so forth.

In various aspects, the processor may be arranged to run an operatingsystem (OS) and various applications. Examples of an OS comprise, forexample, operating systems generally known under the trade name of AppleOS, Microsoft Windows OS, Android OS, and any other proprietary or opensource OS. Examples of applications comprise, for example, a telephoneapplication, a camera (e.g., digital camera, video camera) application,a browser application, a multimedia player application, a gamingapplication, a messaging application (e.g., email, short message,multimedia), a viewer application, and so forth.

In some embodiments, at least one non-transitory computer-readablestorage medium is provided having computer-executable instructionsembodied thereon, wherein, when executed by at least one processor, thecomputer-executable instructions cause the at least one processor toperform embodiments of the methods described herein. Thiscomputer-readable storage medium can be embodied in the memory.

In some embodiments, the memory may comprise any machine-readable orcomputer-readable media capable of storing data, including bothvolatile/non-volatile memory and removable/non-removable memory. Thememory may comprise at least one non-volatile memory unit. Thenon-volatile memory unit is capable of storing one or more softwareprograms. The software programs may contain, for example, applications,user data, device data, and/or configuration data, or combinationstherefore, to name only a few. The software programs may containinstructions executable by the various components of the controlcircuits 112 of the system 100.

For example, memory may comprise read-only memory (ROM), random-accessmemory (RAM), dynamic RAM (DRAM), Double-Data-Rate DRAM (DDR-RAM),synchronous DRAM (SDRAM), static RAM (SRAM), programmable ROM (PROM),erasable programmable ROM (EPROM), electrically erasable programmableROM (EEPROM), flash memory (e.g., NOR or NAND flash memory), contentaddressable memory (CAM), polymer memory (e.g., ferroelectric polymermemory), phase-change memory (e.g., ovonic memory), ferroelectricmemory, silicon-oxide-nitride-oxide-silicon (SONOS) memory, disk memory(e.g., floppy disk, hard drive, optical disk, magnetic disk), or card(e.g., magnetic card, optical card), or any other type of media suitablefor storing information.

In one embodiment, the memory may contain an instruction set, in theform of a file for executing a method of generating one or more timinglibraries as described herein. The instruction set may be stored in anyacceptable form of machine-readable instructions, including source codeor various appropriate programming languages. Some examples ofprogramming languages that may be used to store the instruction setcomprise, but are not limited to: Java, C, C++, C#, Python, Objective-C,Visual Basic, or .NET programming. In some embodiments a compiler orinterpreter is comprised to convert the instruction set into machineexecutable code for execution by the processor.

In some embodiments, the I/O interface may comprise any suitablemechanism or component to at least enable a user to provide input to thecontrol unit 316 of the system 300 and the control unit 316 to provideoutput to the user. For example, the I/O interface may comprise anysuitable input mechanism, including but not limited to, a button,keypad, keyboard, click wheel, touch screen, or motion sensor. In someembodiments, the I/O interface may comprise a capacitive sensingmechanism, or a multi-touch capacitive sensing mechanism (e.g., atouchscreen).

In some embodiments, the I/O interface may comprise a visual peripheraloutput device for providing a display visible to the user. For example,the visual peripheral output device may comprise a screen such as, forexample, a Liquid Crystal Display (LCD) screen, incorporated into thecontrol unit 316 of the system 300. As another example, the visualperipheral output device may comprise a movable display or projectingsystem for providing a display of content on a surface remote from thecontrol unit 316 of the vacuum processing system 100. In someembodiments, the visual peripheral output device can comprise acoder/decoder, also known as a Codec, to convert digital media data intoanalog signals. For example, the visual peripheral output device maycomprise video Codecs, audio Codecs, or any other suitable type ofCodec.

The visual peripheral output device also may comprise display drivers,circuitry for driving display drivers, or both. The visual peripheraloutput device may be operative to display content under the direction ofthe processor. For example, the visual peripheral output device may beable to play media playback information, application screens forapplications implemented on the control unit 316 of the system 300,information regarding ongoing communications operations, informationregarding incoming communications requests, or device operation screens,to name only a few.

In some embodiments, the communications interface may comprise anysuitable hardware, software, or combination of hardware and softwarethat is capable of coupling the control unit 316 of the system 300 toone or more networks and/or additional devices. The communicationsinterface may be arranged to operate with any suitable technique forcontrolling information signals using a desired set of communicationsprotocols, services or operating procedures. The communicationsinterface may comprise the appropriate physical connectors to connectwith a corresponding communications medium, whether wired or wireless.

Systems and methods of communication comprise a network, in accordancewith some embodiments. In various aspects, the network may compriselocal area networks (LAN) as well as wide area networks (WAN) includingwithout limitation Internet, wired channels, wireless channels,communication devices including telephones, computers, wire, radio,optical or other electromagnetic channels, and combinations thereof,including other devices and/or components capable of/associated withcommunicating data. For example, the communication environments comprisein-body communications, various devices, and various modes ofcommunications such as wireless communications, wired communications,and combinations of the same.

Wireless communication modes comprise any mode of communication betweenpoints (e.g., nodes) that utilize, at least in part, wireless technologyincluding various protocols and combinations of protocols associatedwith wireless transmission, data, and devices. The points comprise, forexample, wireless devices such as wireless headsets, audio andmultimedia devices and equipment, such as audio players and multimediaplayers, telephones, including mobile telephones and cordlesstelephones, and computers and computer-related devices and components,such as printers, network-connected machinery, and/or any other suitabledevice or third-party device.

Wired communication modes comprise any mode of communication betweenpoints that utilize wired technology including various protocols andcombinations of protocols associated with wired transmission, data, anddevices. The points comprise, for example, devices such as audio andmultimedia devices and equipment, such as audio players and multimediaplayers, telephones, including mobile telephones and cordlesstelephones, and computers and computer-related devices and components,such as printers, network-connected machinery, and/or any other suitabledevice or third-party device. In various implementations, the wiredcommunication modules may communicate in accordance with a number ofwired protocols. Examples of wired protocols may comprise UniversalSerial Bus (USB) communication, RS-232, RS-422, RS-423, RS-485 serialprotocols, FireWire, Ethernet, Fiber Channel, MIDI, ATA, Serial ATA, PCIExpress, T-1 (and variants), Industry Standard Architecture (ISA)parallel communication, Small Computer System Interface (SCSI)communication, or Peripheral Component Interconnect (PCI) communication,to name only a few examples.

Accordingly, in various aspects, the communications interface maycomprise one or more interfaces such as, for example, a wirelesscommunications interface, a wired communications interface, a networkinterface, a transmit interface, a receive interface, a media interface,a system interface, a component interface, a switching interface, a chipinterface, a controller, and so forth. When implemented by a wirelessdevice or within wireless system, for example, the communicationsinterface may comprise a wireless interface comprising one or moreantennas, transmitters, receivers, transceivers, amplifiers, filters,control logic, and so forth.

In various embodiments, the communications interface may provide voiceand/or data communications functionality in accordance a number ofwireless protocols. Examples of wireless protocols may comprise variouswireless local area network (WLAN) protocols, including the Institute ofElectrical and Electronics Engineers (IEEE) 802.xx series of protocols,such as IEEE 802.11a/b/g/n, IEEE 802.16, IEEE 802.20, and so forth.Other examples of wireless protocols may comprise various wireless widearea network (WWAN) protocols, such as GSM cellular radiotelephonesystem protocols with GPRS, CDMA cellular radiotelephone communicationsystems with 1×RTT, EDGE systems, EV-DO systems, EV-DV systems, HSDPAsystems, and so forth. Further examples of wireless protocols maycomprise wireless personal area network (PAN) protocols, such as anInfrared protocol, a protocol from the Bluetooth Special Interest Group(SIG) series of protocols, including Bluetooth Specification versionsv1.0, v1.1, v1.2, v2.0, v2.0 with Enhanced Data Rate (EDR), as well asone or more Bluetooth Profiles, and so forth. Yet another example ofwireless protocols may comprise near-field communication techniques andprotocols, such as electromagnetic induction (EMI) techniques. Anexample of EMI techniques may comprise passive or active radio-frequencyidentification (RFID) protocols and devices. Other suitable protocolsmay comprise Ultra Wide Band (UWB), Digital Office (DO), Digital Home,Trusted Platform Module (TPM), ZigBee, and so forth.

In some embodiments, the control unit 316 of the system 300 may comprisea system bus that couples various system components including theprocessor, the memory, and the I/O interface. The system bus can be anyof several types of bus structure(s) including a memory bus or memorycontroller, a peripheral bus or external bus, and/or a local bus usingany variety of available bus architectures including, but not limitedto, 9-bit bus, Industrial Standard Architecture (ISA), Micro-ChannelArchitecture (MCA), Extended ISA (EISA), Intelligent Drive Electronics(IDE), VESA Local Bus (VLB), Personal Computer Memory Card InternationalAssociation (PCMCIA) Bus, Small Computer System Interface (SCSI) orother proprietary bus, or any custom bus suitable for computing deviceapplications.

FIG. 4 illustrates a flowchart of a method 400 to use a pressuremonitoring sensing tape 208 in a vacuum processing system 100 to monitorthe closing condition of a vacuum valve 106 in a vacuum processingchamber 102, in accordance with some embodiments of the presentdisclosure. It is understood that additional operations may be providedbefore, during, and after the method 400 of FIG. 4, and that some otheroperations may be omitted or only briefly described herein.

The method 400 starts with operation 402 in which a vacuum processingchamber 102 is prepared for a vacuum process, according to someembodiments. This preparation includes, but not limited to, cleaning thevacuum processing chamber 102 using in-situ dry etching, configuring apressure in the vacuum processing chamber 102 using a pressure controlunit 110, configuring a temperature on a stage 116, configuring anenvironment in the vacuum processing chamber 102 by providing at leastone gas to the vacuum processing chamber 102, and configuring a reactionrecipe using a reaction control unit 316, in accordance with someembodiments.

The method 400 continues with operation 404, in which the vacuumprocessing chamber 102 receives a semiconductor wafer 112 through atransfer port 104 for processing, according to some embodiments. In someembodiments, a vacuum valve 106 is open so that a wafer transfermechanism 114 delivers the semiconductor wafer 112 from a load lockchamber or another processing chamber to the vacuum processing chamber102. The semiconductor wafer 112 is delivered to and secured on thewafer stage 116. The wafer transfer mechanism 114 retracts from thevacuum processing chamber 102 and the vacuum valve 106 closes to make aseal with a mating surface 206 on the vacuum processing chamber 102through a pressure monitoring tape 208, in some embodiments.

The method 400 continues with operation 406, in which a pressure profilemapping is performed using a pressure monitoring tape 208, according tosome embodiments. The pressure monitoring tape 208 comprises a pluralityof sensing elements 304. The pressure profile between a surface of ano-ring 204 and a top surface of the pressure monitoring tap is measured.Depending on the sensing technology of the sensing elements 304, astress or a strain applied on the sensing elements creates a measurableelectrical signal that can be collected by a data acquisition unit 310.A pressure value from each of the sensing elements 304 can be obtainedfrom the electrical signal with proper calibration, e.g., contact area,by a data processing unit 312 to create a pressure profile mapping, insome embodiments. A 2-dimensional or a 3-dimensional pressure profile,i.e., pressure value versus position, can be then displayed on a screenattached to a local computer 314.

The method 400 continues with operation 408, in which pressure data iscompared to a predefined or user-preconfigured threshold values todetermine the closing status of the vacuum valve 106, according to someembodiments. The local computer 314 is further configured to analyze thepressure profile mapping to obtain values such as an average pressurevalue, a maximum pressure value, a minimum pressure value, a standarddeviation value, etc. These values are then compared to predeterminedthreshold values to determine the alignment between the vacuum valve 106and the mating surface 206 and the closing condition of the vacuum valve106. If the measured values are within the predetermined thresholdvalues, the local computer 314 instructs the reaction control unit tocontinue with operation 510 in which the vacuum processing is performedon the semiconductor wafer 112. If the measured values are out of thepredetermined threshold values, the method continues with operation 512in which the local computer 314 triggers a maintenance procedure usingthe reaction control unit 316, for example examining the closingmechanism on the vacuum valve 106, cleaning or replacing the o-ring 204,etc. After the maintenance procedure is performed, the pressure profilemapping is measured again through operation 506 and the vacuumprocessing is further performed on the semiconductor wafer 112 when themeasured values are within the predetermined threshold values, in someembodiments.

The preceding merely illustrates the principles of the disclosure. Itwill thus be appreciated that those of ordinary skill in the art will beable to devise various arrangements which, although not explicitlydescribed or shown herein, embody the principles of the disclosure andare included within its spirit and scope. Furthermore, all examples andconditional language recited herein are principally intended expresslyto be only for pedagogical purposes and to aid the reader inunderstanding the principles of the disclosure and the inventiveconcepts, and are to be construed as being without limitation to suchspecifically recited examples and conditions. Moreover, all statementsherein reciting principles, aspects, and embodiments of the disclosure,as well as specific examples thereof, are intended to encompass bothstructural and functional equivalents thereof. Additionally, it isintended that such equivalents include both currently known equivalentsand equivalents developed in the future, i.e., any elements developedthat perform the same function, regardless of structure.

This description of the exemplary embodiments is set to be understood inconnection with the figures of the accompanying drawing, which are to beconsidered part of the entire written description. In the description,relative terms such as “lower,” “upper,” “horizontal,” “vertical,”“above,” “below,” “up,” “down,” “top” and “bottom” as well asderivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,”etc.) should be construed to refer to the orientation as then describedor as shown in the drawing under discussion. These relative terms arefor convenience of description and do not require that the apparatus beconstructed or operated in a particular orientation.

In an embodiment, a vacuum valve closing condition monitoring system,comprising: a vacuum valve comprising at least one sealing O-ring; and apressure monitoring tape on a mating surface on a vacuum processingchamber, wherein the pressure monitoring tape is configured to perform apressure profile mapping between the mating surface on the vacuumprocessing chamber and a surface of the at least one sealing O-ring onthe vacuum valve to determine a closing condition of the vacuum valve.

In another embodiment, a vacuum valve closing condition monitoringmethod, comprising: closing a vacuum valve on a vacuum processingchamber, wherein the vacuum valve comprises at least one sealing O-ring;and determining a closing condition of the vacuum valve using a pressuremonitoring tape, wherein the pressure monitoring tape is configured on amating surface on the vacuum processing chamber to perform the pressureprofile mapping between the mating surface on the vacuum processingchamber and a surface of the at least one sealing O-ring on the vacuumvalve.

Yet in another embodiment, a vacuum valve closing condition monitoringsystem comprising: a vacuum valve comprising at least one sealingO-ring; a pressure monitoring tape configured between a mating surfaceon a vacuum processing chamber and a surface of the at least one sealingO-ring on the vacuum valve; a data acquisition unit configured tocollect a plurality of signals from a plurality of pressure sensingelements on the pressure monitoring tape, respectively; a dataprocessing unit configured to process the plurality of signals from theplurality of pressure sensing elements to determine a plurality ofpressure values, respectively; and a local computer configured todetermine the closing condition of the vacuum valve based on theplurality of pressure values.

Although the disclosure has been described in terms of exemplaryembodiments, it is not limited thereto. Rather, the appended claimsshould be construed broadly, to include other variants and embodimentsof the disclosure, which may be made by those of ordinary skill in theart without departing from the scope and range of equivalents of thedisclosure.

What is claimed is:
 1. A vacuum valve monitoring system, comprising: avacuum valve comprising at least one sealing O-ring; and a pressuremonitoring tape attached to a mating surface of a vacuum processingchamber, wherein the pressure monitoring tape is disposed between the atleast one sealing O-ring and the mating surface and is configured toperform a pressure profile mapping between the mating surface on thevacuum processing chamber and a surface of the at least one sealingO-ring on the vacuum valve to determine a closing condition of thevacuum valve, wherein at least a portion of a surface of the at leastone sealing O-ring is coated with a film of low vapor pressure grease,wherein the pressure monitoring tape comprises a plurality of pressuresensing elements.
 2. The system of claim 1, wherein the vacuum valve isconfigured to open and close a transfer port within the vacuumprocessing chamber.
 3. The system of claim 1, further comprising a localcomputer configured to determine based on the pressure profile mapping aplurality of pressure values comprising an average pressure value, amaximum pressure value, a minimum pressure value and a deviation ofpressure values for the at least one sealing O-ring, wherein the localcomputer determines whether one or more of the plurality of pressurevalues are within predefined threshold values.
 4. The system of claim 3,wherein the local computer is further configured to compare theplurality of pressure values to a plurality of predetermined thresholdpressure values; and determine the closing condition of the vacuumvalve.
 5. The system of claim 1, wherein the pressure monitoring tape isflexible.
 6. The system of claim 1, wherein each of the plurality ofpressure sensing elements comprises at least one of the following:capacitive, piezoresistive, and piezoelectric tactile sensors.
 7. Thesystem of claim 1, wherein each of the plurality of pressure sensingelements comprises a thin film sensor.
 8. The system of claim 1, furthercomprising: a data acquisition unit to collect a respective plurality ofsignals from each of a respective plurality of pressure sensing elementson the pressure monitoring tape; and a data processing unit to processthe respective plurality of signals
 9. A vacuum valve monitoring method,comprising: closing a vacuum valve on a vacuum processing chamber,wherein the vacuum valve comprises at least one sealing O-ring;determining a closing condition of the vacuum valve using a pressuremonitoring tape, wherein the pressure monitoring tape is configured on amating surface that is disposed on a wall of the vacuum processingchamber to perform a pressure profile mapping between the mating surfacethat is disposed on the wall of the vacuum processing chamber and asurface of the at least one sealing O-ring on the vacuum valve, whereinthe pressure monitoring tape is disposed between the at least onesealing O-ring and the mating surface, wherein at least a portion of asurface of the at least one sealing O-ring is coated with a film of lowvapor pressure grease; determining based on the pressure profile mappinga plurality of pressure values for the at least one sealing O-ring; anddetermining whether one or more of the plurality of pressure values arewithin predefined threshold values.
 10. The method of claim 9, whereinthe vacuum valve is configured to open and close a transfer port withinthe vacuum processing chamber.
 11. The method of claim 9, wherein thepressure monitoring tape comprises a plurality of pressure sensingelements.
 12. The method of claim 11, wherein each of the plurality ofpressure sensing elements comprises at least one of the following:capacitive, piezoresistive, and piezoelectric tactile sensors.
 13. Themethod of claim 11, wherein each of the plurality of pressure sensingelements comprises a thin film sensor.
 14. The method of claim 9,wherein the determining further comprising: collecting a respectiveplurality of signals from a respective plurality of pressure sensingelements on the pressure monitoring tape; and processing the respectiveplurality of signals from the respective plurality of pressure sensingelements to determine the pressure profile mapping.
 15. A vacuum valvemonitoring system comprising: a vacuum valve comprising at least onesealing O-ring; a pressure monitoring tape disposed between a matingsurface of a vacuum processing chamber and a surface of the at least onesealing O-ring on the vacuum valve, wherein at least a portion of asurface of the at least one sealing O-ring is coated with a film of lowvapor pressure grease; a data acquisition unit configured to collect arespective plurality of signals from each of a respective plurality ofpressure sensing elements on the pressure monitoring tape; a dataprocessing unit configured to process the respective plurality ofsignals from the respective plurality of pressure sensing elements; anda local computer configured to determine a closing condition of thevacuum valve based on a plurality of pressure values obtained from theplurality of signals, wherein the local computer determines whether theone or more of the plurality of pressure values are within predefinedthreshold values.
 16. The system of claim 15, wherein the pressuremonitoring tape is flexible.
 17. The system of claim 15, wherein each ofthe plurality of pressure sensing elements comprises at least one of thefollowing: capacitive, piezoresistive, and piezoelectric tactilesensors.
 18. The system of claim 15, wherein each of the plurality ofpressure sensing elements comprises a thin film sensor.
 19. The systemof claim 15, wherein the vacuum valve is configured to open and close atransfer port within the vacuum processing chamber.
 20. The system ofclaim 15, wherein if the one or more of the plurality of pressure valuesare within the predefined threshold values, instruct the vacuumprocessing chamber to perform vacuum processing, and wherein if the oneor more of the plurality of pressure values are not within thepredefined threshold values, alarm an operator and trigger apreconfigured maintenance procedure.